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1 \input texinfo.tex
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2
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3 @c $Id: widget.texi,v 1.1 1997/02/02 04:58:52 steve Exp $
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4
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5 @c %**start of header
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6 @setfilename widget
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7 @settitle The Emacs Widget Library
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8 @iftex
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9 @afourpaper
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10 @headings double
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11 @end iftex
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12 @c %**end of header
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13
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14 @node Top, Introduction, (dir), (dir)
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15 @comment node-name, next, previous, up
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16 @top The Emacs Widget Library
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17
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18 Version: 1.20
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19
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20 @menu
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21 * Introduction::
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22 * User Interface::
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23 * Programming Example::
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24 * Setting Up the Buffer::
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25 * Basic Types::
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26 * Sexp Types::
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27 * Widget Properties::
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28 * Defining New Widgets::
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29 * Widget Wishlist.::
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30 @end menu
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31
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32 @node Introduction, User Interface, Top, Top
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33 @comment node-name, next, previous, up
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34 @section Introduction
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35
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36 Most graphical user interface toolkits, such as Motif and XView, provide
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37 a number of standard user interface controls (sometimes known as
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38 `widgets' or `gadgets'). Emacs doesn't really support anything like
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39 this, except for an incredible powerful text ``widget''. On the other
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40 hand, Emacs does provide the necessary primitives to implement many
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41 other widgets within a text buffer. The @code{widget} package
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42 simplifies this task.
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43
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44 The basic widgets are:
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45
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46 @table @code
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47 @item link
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48 Areas of text with an associated action. Intended for hypertext links
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49 embedded in text.
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50 @item push-button
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51 Like link, but intended for stand-alone buttons.
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52 @item editable-field
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53 An editable text field. It can be either variable or fixed length.
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54 @item menu-choice
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55 Allows the user to choose one of multiple options from a menu, each
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56 option is itself a widget. Only the selected option will be visible in
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57 the buffer.
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58 @item radio-button-choice
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59 Allows the user to choose one of multiple options by pushing radio
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60 buttons. The options are implemented as widgets. All options will be
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61 visible in the buffer.
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62 @item item
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63 A simple constant widget intended to be used in the @code{menu-choice} and
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64 @code{radio-button-choice} widgets.
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65 @item choice-item
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66 An button item only intended for use in choices. When pushed, the user
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67 will be asked to select another option from the choice widget.
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68 @item toggle
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69 A simple @samp{on}/@samp{off} switch.
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70 @item checkbox
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71 A checkbox (@samp{[ ]}/@samp{[X]}).
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72 @item editable-list
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73 Create an editable list. The user can insert or delete items in the
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74 list. Each list item is itself a widget.
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75 @end table
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76
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77 Now of what possible use can support for widgets be in a text editor?
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78 I'm glad you asked. The answer is that widgets are useful for
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79 implementing forms. A @dfn{form} in emacs is a buffer where the user is
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80 supposed to fill out a number of fields, each of which has a specific
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81 meaning. The user is not supposed to change or delete any of the text
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82 between the fields. Examples of forms in Emacs are the @file{forms}
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83 package (of course), the customize buffers, the mail and news compose
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84 modes, and the @sc{html} form support in the @file{w3} browser.
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85
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86 The advantages for a programmer of using the @code{widget} package to
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87 implement forms are:
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88
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89 @enumerate
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90 @item
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91 More complex field than just editable text are supported.
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92 @item
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93 You can give the user immediate feedback if he enters invalid data in a
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94 text field, and sometimes prevent entering invalid data.
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95 @item
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96 You can have fixed sized fields, thus allowing multiple field to be
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97 lined up in columns.
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98 @item
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99 It is simple to query or set the value of a field.
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100 @item
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101 Editing happens in buffer, not in the mini-buffer.
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102 @item
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103 Packages using the library get a uniform look, making them easier for
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104 the user to learn.
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105 @item
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106 As support for embedded graphics improve, the widget library will
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107 extended to support it. This means that your code using the widget
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108 library will also use the new graphic features by automatic.
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109 @end enumerate
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110
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111 In order to minimize the code that is loaded by users who does not
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112 create any widgets, the code has been split in two files:
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113
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114 @table @file
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115 @item widget.el
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116 This will declare the user variables, define the function
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117 @code{widget-define}, and autoload the function @code{widget-create}.
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118 @item widget-edit.el
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119 Everything else is here, there is no reason to load it explicitly, as
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120 it will be autoloaded when needed.
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121 @end table
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122
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123 @node User Interface, Programming Example, Introduction, Top
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124 @comment node-name, next, previous, up
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125 @section User Interface
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126
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127 A form consist of read only text for documentation and some fields,
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128 where each the fields contain two parts, as tag and a value. The tags
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129 are used to identify the fields, so the documentation can refer to the
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130 foo field, meaning the field tagged with @samp{Foo}. Here is an example
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131 form:
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132
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133 @example
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134 Here is some documentation.
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135
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136 Name: @i{My Name} @strong{Choose}: This option
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137 Address: @i{Some Place
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138 In some City
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139 Some country.}
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140
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141 See also @b{_other work_} for more information.
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142
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143 Numbers: count to three below
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144 @b{[INS]} @b{[DEL]} @i{One}
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145 @b{[INS]} @b{[DEL]} @i{Eh, two?}
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146 @b{[INS]} @b{[DEL]} @i{Five!}
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147 @b{[INS]}
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148
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149 Select multiple:
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150
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151 @b{[X]} This
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152 @b{[ ]} That
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153 @b{[X]} Thus
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154
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155 Select one:
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156
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157 @b{(*)} One
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158 @b{( )} Another One.
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159 @b{( )} A Final One.
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160
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161 @b{[Apply Form]} @b{[Reset Form]}
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162 @end example
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163
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164 The top level widgets in is example are tagged @samp{Name},
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165 @samp{Choose}, @samp{Address}, @samp{_other work_}, @samp{Numbers},
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166 @samp{Select multiple}, @samp{Select one}, @samp{[Apply Form]}, and
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167 @samp{[Reset Form]}. There are basically two thing the user can do within
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168 a form, namely editing the editable text fields and activating the
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169 buttons.
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170
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171 @subsection Editable Text Fields
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172
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173 In the example, the value for the @samp{Name} is most likely displayed
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174 in an editable text field, and so are values for each of the members of
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175 the @samp{Numbers} list. All the normal Emacs editing operations are
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176 available for editing these fields. The only restriction is that each
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177 change you make must be contained within a single editable text field.
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178 For example, capitalizing all text from the middle of one field to the
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179 middle of another field is prohibited.
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180
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181 Editing text fields are created by the @code{editable-field} widget.
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182
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183 The editing text fields are highlighted with the
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184 @code{widget-field-face} face, making them easy to find.
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185
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186 @deffn Face widget-field-face
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187 Face used for other editing fields.
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188 @end deffn
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189
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190 @subsection Buttons
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191
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192 Some portions of the buffer have an associated @dfn{action}, which can
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193 be @dfn{activated} by a standard key or mouse command. These portions
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194 are called @dfn{buttons}. The default commands for activating a button
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195 are:
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196
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197 @table @kbd
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198 @item @key{RET}
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199 @deffn Command widget-button-press @var{pos} &optional @var{event}
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200 Activate the button at @var{pos}, defaulting to point.
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201 If point is not located on a button, activate the binding in
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202 @code{widget-global-map} (by default the global map).
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203 @end deffn
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204
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205 @item mouse-2
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206 @deffn Command widget-button-click @var{event}
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207 Activate the button at the location of the mouse pointer. If the mouse
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208 pointer is located in an editable text field, activate the binding in
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209 @code{widget-global-map} (by default the global map).
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210 @end deffn
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211 @end table
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212
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213 There are several different kind of buttons, all of which are present in
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214 the example:
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215
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216 @table @emph
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217 @item The Option Field Tags.
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218 When you activate one of these buttons, you will be asked to choose
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219 between a number of different options. This is how you edit an option
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220 field. Option fields are created by the @code{menu-choice} widget. In
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221 the example, @samp{@b{Choose}} is an option field tag.
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222 @item The @samp{@b{[INS]}} and @samp{@b{[DEL]}} buttons.
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223 Activating these will insert or delete elements from a editable list.
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224 The list is created by the @code{editable-list} widget.
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225 @item Embedded Buttons.
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226 The @samp{@b{_other work_}} is an example of an embedded
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227 button. Embedded buttons are not associated with a fields, but can serve
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228 any purpose, such as implementing hypertext references. They are
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229 usually created by the @code{link} widget.
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230 @item The @samp{@b{[ ]}} and @samp{@b{[X]}} buttons.
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231 Activating one of these will convert it to the other. This is useful
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232 for implementing multiple-choice fields. You can create it wit
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233 @item The @samp{@b{( )}} and @samp{@b{(*)}} buttons.
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234 Only one radio button in a @code{radio-button-choice} widget can be selected at any
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235 time. When you push one of the unselected radio buttons, it will be
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236 selected and the previous selected radio button will become unselected.
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237 @item The @samp{@b{[Apply Form]}} @samp{@b{[Reset Form]}} buttons.
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238 These are explicit buttons made with the @code{push-button} widget. The main
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239 difference from the @code{link} widget is that the buttons are intended
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240 to be displayed more like buttons in a GUI, once Emacs grows powerful
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241 enough.
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242 @end table
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243
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244 To make them easier to locate, buttons are emphasized in the buffer.
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245
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246 @deffn Face widget-button-face
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247 Face used for buttons.
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248 @end deffn
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249
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250 @defopt widget-mouse-face
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251 Face used for buttons when the mouse pointer is above it.
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252 @end defopt
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253
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254 @subsection Navigation
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255
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256 You can use all the normal Emacs commands to move around in a form
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257 buffer, plus you will have these additional commands:
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258
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259 @table @kbd
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260 @item @key{TAB}
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261 @deffn Command widget-forward &optional count
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262 Move point @var{count} buttons or editing fields forward.
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263 @end deffn
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264 @item @key{M-TAB}
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265 @deffn Command widget-backward &optional count
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266 Move point @var{count} buttons or editing fields backward.
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267 @end deffn
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268 @end table
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269
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270 @node Programming Example, Setting Up the Buffer, User Interface, Top
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271 @comment node-name, next, previous, up
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272 @section Programming Example
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273
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274 Here is the code to implement the user interface example (see @ref{User
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275 Interface}).
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276
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277 @lisp
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278 (require 'widget)
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279
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280 (eval-when-compile
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281 (require 'widget-edit))
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282
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283 (defvar widget-example-repeat)
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284
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285 (defun widget-example ()
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286 "Create the widgets from the Widget manual."
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287 (interactive)
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288 (switch-to-buffer "*Widget Example*")
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289 (kill-all-local-variables)
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290 (make-local-variable 'widget-example-repeat)
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291 (let ((inhibit-read-only t))
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292 (erase-buffer))
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293 (widget-insert "Here is some documentation.\n\nName: ")
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294 (widget-create 'editable-field
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295 :size 13
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296 "My Name")
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297 (widget-create 'menu-choice
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298 :tag "Choose"
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299 :value "This"
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300 :help-echo "Choose me, please!"
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301 :notify (lambda (widget &rest ignore)
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302 (message "%s is a good choice!"
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303 (widget-value widget)))
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304 '(item :tag "This option" :value "This")
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305 '(choice-item "That option")
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306 '(editable-field :menu-tag "No option" "Thus option"))
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307 (widget-insert "Address: ")
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308 (widget-create 'editable-field
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309 "Some Place\nIn some City\nSome country.")
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310 (widget-insert "\nSee also ")
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311 (widget-create 'link
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312 :notify (lambda (&rest ignore)
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313 (widget-value-set widget-example-repeat
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314 '("En" "To" "Tre"))
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315 (widget-setup))
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316 "other work")
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317 (widget-insert " for more information.\n\nNumbers: count to three below\n")
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318 (setq widget-example-repeat
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319 (widget-create 'editable-list
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320 :entry-format "%i %d %v"
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321 :notify (lambda (widget &rest ignore)
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322 (let ((old (widget-get widget
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323 ':example-length))
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324 (new (length (widget-value widget))))
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325 (unless (eq old new)
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326 (widget-put widget ':example-length new)
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327 (message "You can count to %d." new))))
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328 :value '("One" "Eh, two?" "Five!")
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329 '(editable-field :value "three")))
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330 (widget-insert "\n\nSelect multiple:\n\n")
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331 (widget-create 'checkbox t)
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332 (widget-insert " This\n")
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333 (widget-create 'checkbox nil)
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334 (widget-insert " That\n")
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335 (widget-create 'checkbox
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336 :notify (lambda (&rest ignore) (message "Tickle"))
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337 t)
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338 (widget-insert " Thus\n\nSelect one:\n\n")
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339 (widget-create 'radio-button-choice
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340 :value "One"
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341 :notify (lambda (widget &rest ignore)
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342 (message "You selected %s"
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343 (widget-value widget)))
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344 '(item "One") '(item "Anthor One.") '(item "A Final One."))
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345 (widget-insert "\n")
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346 (widget-create 'push-button
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347 :notify (lambda (&rest ignore)
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348 (if (= (length (widget-value widget-example-repeat))
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349 3)
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350 (message "Congratulation!")
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351 (error "Three was the count!")))
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352 "Apply Form")
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353 (widget-insert " ")
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354 (widget-create 'push-button
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355 :notify (lambda (&rest ignore)
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356 (widget-example))
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357 "Reset Form")
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358 (widget-insert "\n")
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359 (use-local-map widget-keymap)
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360 (widget-setup))
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361 @end lisp
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362
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363 @node Setting Up the Buffer, Basic Types, Programming Example, Top
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364 @comment node-name, next, previous, up
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365 @section Setting Up the Buffer
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366
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367 Widgets are created with @code{widget-create}, which returns a
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368 @dfn{widget} object. This object can be queried and manipulated by
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369 other widget functions, until it is deleted with @code{widget-delete}.
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370 After the widgets have been created, @code{widget-setup} must be called
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371 to enable them.
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372
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373 @defun widget-create type [ keyword argument ]@dots{}
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374 Create and return a widget of type @var{type}.
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375 The syntax for the @var{type} argument is described in @ref{Basic Types}.
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376
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377 The keyword arguments can be used to overwrite the keyword arguments
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378 that are part of @var{type}.
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379 @end defun
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380
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381 @defun widget-delete widget
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382 Delete @var{widget} and remove it from the buffer.
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383 @end defun
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384
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385 @defun widget-setup
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386 Setup a buffer to support widgets.
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387
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388 This should be called after creating all the widgets and before allowing
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389 the user to edit them.
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390 @refill
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391 @end defun
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392
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393 If you want to insert text outside the widgets in the form, the
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394 recommended way to do that is with @code{widget-insert}.
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395
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396 @defun widget-insert
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397 Insert the arguments, either strings or characters, at point.
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398 The inserted text will be read only.
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399 @end defun
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400
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401 There is a standard widget keymap which you might find useful.
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402
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403 @defvr Const widget-keymap
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404 A keymap with the global keymap as its parent.@br
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405 @key{TAB} and @kbd{C-@key{TAB}} are bound to @code{widget-forward} and
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406 @code{widget-backward}, respectively. @kbd{@key{RET}} and @kbd{mouse-2}
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407 are bound to @code{widget-button-press} and
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408 @code{widget-button-}.@refill
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409 @end defvr
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410
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411 @defvar widget-global-map
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412 Keymap used by @code{widget-button-press} and @code{widget-button-click}
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413 when not on a button. By default this is @code{global-map}.
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414 @end defvar
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415
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416 @node Basic Types, Sexp Types, Setting Up the Buffer, Top
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417 @comment node-name, next, previous, up
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418 @section Basic Types
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419
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420 The syntax of a type specification is given below:
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421
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422 @example
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423 NAME ::= (NAME [KEYWORD ARGUMENT]... ARGS)
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424 | NAME
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425 @end example
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426
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427 Where, @var{name} is a widget name, @var{keyword} is the name of a
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428 property, @var{argument} is the value of the property, and @var{args}
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429 are interpreted in a widget specific way.
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430
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431 There following keyword arguments that apply to all widgets:
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432
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433 @table @code
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434 @item :value
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435 The initial value for widgets of this type.
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436
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437 @item :format
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438 This string will be inserted in the buffer when you create a widget.
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439 The following @samp{%} escapes are available:
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440
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441 @table @samp
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442 @item %[
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443 @itemx %]
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444 The text inside will be marked as a button.
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445
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446 @item %@{
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447 @itemx %@}
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448 The text inside will be displayed with the face specified by
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449 @code{:sample-face}.
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450
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451 @item %v
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452 This will be replaces with the buffer representation of the widgets
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453 value. What this is depends on the widget type.
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454
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455 @item %d
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456 Insert the string specified by @code{:doc} here.
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457
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458 @item %h
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459 Like @samp{%d}, with the following modifications: If the documentation
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460 string is more than one line, it will add a button which will toggle
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461 between showing only the first line, and showing the full text.
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462 Furthermore, if there is no @code{:doc} property in the widget, it will
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463 instead examine the @code{:documentation-property} property. If it is a
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464 lambda expression, it will be called with the widget's value as an
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465 argument, and the result will be used as the documentation text.
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466
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467 @item %t
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468 Insert the string specified by @code{:tag} here, or the @code{princ}
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469 representation of the value if there is no tag.
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470
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471 @item %%
|
|
472 Insert a literal @samp{%}.
|
|
473 @end table
|
|
474
|
|
475 @item :button-face
|
|
476 Face used to highlight text inside %[ %] in the format.
|
|
477
|
|
478 @item :doc
|
|
479 The string inserted by the @samp{%d} escape in the format
|
|
480 string.
|
|
481
|
|
482 @item :tag
|
|
483 The string inserted by the @samp{%t} escape in the format
|
|
484 string.
|
|
485
|
|
486 @item :help-echo
|
|
487 Message displayed whenever you move to the widget with either
|
|
488 @code{widget-forward} or @code{widget-backward}.
|
|
489
|
|
490 @item :indent
|
|
491 An integer indicating the absolute number of spaces to indent children
|
|
492 of this widget.
|
|
493
|
|
494 @item :offset
|
|
495 An integer indicating how many extra spaces to add to the widget's
|
|
496 grandchildren compared to this widget.
|
|
497
|
|
498 @item :extra-offset
|
|
499 An integer indicating how many extra spaces to add to the widget's
|
|
500 children compared to this widget.
|
|
501
|
|
502 @item :notify
|
|
503 A function called each time the widget or a nested widget is changed.
|
|
504 The function is called with two or three arguments. The first argument
|
|
505 is the widget itself, the second argument is the widget that was
|
|
506 changed, and the third argument is the event leading to the change, if
|
|
507 any.
|
|
508
|
|
509 @item :menu-tag
|
|
510 Tag used in the menu when the widget is used as an option in a
|
|
511 @code{menu-choice} widget.
|
|
512
|
|
513 @item :menu-tag-get
|
|
514 Function used for finding the tag when the widget is used as an option
|
|
515 in a @code{menu-choice} widget. By default, the tag used will be either the
|
|
516 @code{:menu-tag} or @code{:tag} property if present, or the @code{princ}
|
|
517 representation of the @code{:value} property if not.
|
|
518
|
|
519 @item :match
|
|
520 Should be a function called with two arguments, the widget and a value,
|
|
521 and returning non-nil if the widget can represent the specified value.
|
|
522
|
|
523 @item :validate
|
|
524 A function which takes a widget as an argument, and return nil if the
|
|
525 widgets current value is valid for the widget. Otherwise, it should
|
|
526 return the widget containing the invalid data, and set that widgets
|
|
527 @code{:error} property to a string explaining the error.
|
|
528
|
|
529 @item :parent
|
|
530 The parent of a nested widget (e.g. a @code{menu-choice} item or an element of a
|
|
531 @code{editable-list} widget).
|
|
532 @end table
|
|
533
|
|
534 @menu
|
|
535 * link::
|
|
536 * url-link::
|
|
537 * info-link::
|
|
538 * push-button::
|
|
539 * editable-field::
|
|
540 * text::
|
|
541 * menu-choice::
|
|
542 * radio-button-choice::
|
|
543 * item::
|
|
544 * choice-item::
|
|
545 * toggle::
|
|
546 * checkbox::
|
|
547 * checklist::
|
|
548 * editable-list::
|
|
549 @end menu
|
|
550
|
|
551 @node link, url-link, Basic Types, Basic Types
|
|
552 @comment node-name, next, previous, up
|
|
553 @subsection The @code{link} Widget
|
|
554
|
|
555 Syntax:
|
|
556
|
|
557 @example
|
|
558 TYPE ::= (link [KEYWORD ARGUMENT]... [ VALUE ])
|
|
559 @end example
|
|
560
|
|
561 The @var{value}, if present, is used to initialize the @code{:value}
|
|
562 property. The value should be a string, which will be inserted in the
|
|
563 buffer.
|
|
564
|
|
565 @node url-link, info-link, link, Basic Types
|
|
566 @comment node-name, next, previous, up
|
|
567 @subsection The @code{url-link} Widget
|
|
568
|
|
569 Syntax:
|
|
570
|
|
571 @example
|
|
572 TYPE ::= (url-link [KEYWORD ARGUMENT]... URL)
|
|
573 @end example
|
|
574
|
|
575 When this link is activated, the @sc{www} browser specified by
|
|
576 @code{browse-url-browser-function} will be called with @var{url}.
|
|
577
|
|
578 @node info-link, push-button, url-link, Basic Types
|
|
579 @comment node-name, next, previous, up
|
|
580 @subsection The @code{info-link} Widget
|
|
581
|
|
582 Syntax:
|
|
583
|
|
584 @example
|
|
585 TYPE ::= (info-link [KEYWORD ARGUMENT]... ADDRESS)
|
|
586 @end example
|
|
587
|
|
588 When this link is activated, the build-in info browser is started on
|
|
589 @var{address}.
|
|
590
|
|
591 @node push-button, editable-field, info-link, Basic Types
|
|
592 @comment node-name, next, previous, up
|
|
593 @subsection The @code{push-button} Widget
|
|
594
|
|
595 Syntax:
|
|
596
|
|
597 @example
|
|
598 TYPE ::= (push-button [KEYWORD ARGUMENT]... [ VALUE ])
|
|
599 @end example
|
|
600
|
|
601 The @var{value}, if present, is used to initialize the @code{:value}
|
|
602 property. The value should be a string, which will be inserted in the
|
|
603 buffer.
|
|
604
|
|
605 @node editable-field, text, push-button, Basic Types
|
|
606 @comment node-name, next, previous, up
|
|
607 @subsection The @code{editable-field} Widget
|
|
608
|
|
609 Syntax:
|
|
610
|
|
611 @example
|
|
612 TYPE ::= (editable-field [KEYWORD ARGUMENT]... [ VALUE ])
|
|
613 @end example
|
|
614
|
|
615 The @var{value}, if present, is used to initialize the @code{:value}
|
|
616 property. The value should be a string, which will be inserted in
|
|
617 field. This widget will match all string values.
|
|
618
|
|
619 The following extra properties are recognized.
|
|
620
|
|
621 @table @code
|
|
622 @item :size
|
|
623 The width of the editable field.@br
|
|
624 By default the field will reach to the end of the line.
|
|
625
|
|
626 @item :value-face
|
|
627 Face used for highlighting the editable field. Default is
|
|
628 @code{widget-field-face}.
|
|
629
|
|
630 @item :keymap
|
|
631 Keymap used in the editable field. @code{widget-keymap} will allow you
|
|
632 to use normal editing commands, even if these has been suppressed in the
|
|
633 current buffer.
|
|
634
|
|
635 @item :hide-front-space
|
|
636 @itemx :hide-rear-space
|
|
637 In order to keep track of the editable field, emacs places an invisible
|
|
638 space character in front of the field, and for fixed sized fields also
|
|
639 in the rear end of the field. For fields that extent to the end of the
|
|
640 line, the terminating linefeed serves that purpose instead.
|
|
641
|
|
642 Emacs will try to make the spaces intangible when it is safe to do so.
|
|
643 Intangible means that the cursor motion commands will skip over the
|
|
644 character as if it didn't exist. This is safe to do when the text
|
|
645 preceding or following the widget cannot possible change during the
|
|
646 lifetime of the @code{editable-field} widget. The preferred way to tell
|
|
647 Emacs this, is to add text to the @code{:format} property around the
|
|
648 value. For example @code{:format "Tag: %v "}.
|
|
649
|
|
650 You can overwrite the internal safety check by setting the
|
|
651 @code{:hide-front-space} or @code{:hide-rear-space} properties to
|
|
652 non-nil. This is not recommended. For example, @emph{all} text that
|
|
653 belongs to a widget (i.e. is created from its @code{:format} string) will
|
|
654 change whenever the widget changes its value.
|
|
655
|
|
656 @end table
|
|
657
|
|
658 @node text, menu-choice, editable-field, Basic Types
|
|
659 @comment node-name, next, previous, up
|
|
660 @subsection The @code{text} Widget
|
|
661
|
|
662 This is just like @code{editable-field}, but intended for multiline text
|
|
663 fields.
|
|
664
|
|
665 @node menu-choice, radio-button-choice, text, Basic Types
|
|
666 @comment node-name, next, previous, up
|
|
667 @subsection The @code{menu-choice} Widget
|
|
668
|
|
669 Syntax:
|
|
670
|
|
671 @example
|
|
672 TYPE ::= (menu-choice [KEYWORD ARGUMENT]... TYPE ... )
|
|
673 @end example
|
|
674
|
|
675 The @var{type} arguments represents each possible choice. The widgets
|
|
676 value of will be the value of the chosen @var{type} argument. This
|
|
677 widget will match any value that matches at least one of the specified
|
|
678 @var{type} arguments.
|
|
679
|
|
680 @table @code
|
|
681 @item :void
|
|
682 Widget type used as a fallback when the value does not match any of the
|
|
683 specified @var{type} arguments.
|
|
684
|
|
685 @item :case-fold
|
|
686 Set this to nil if you don't want to ignore case when prompting for a
|
|
687 choice through the minibuffer.
|
|
688
|
|
689 @item :children
|
|
690 A list whose car is the widget representing the currently chosen type in
|
|
691 the buffer.
|
|
692
|
|
693 @item :choice
|
|
694 The current chosen type
|
|
695
|
|
696 @item :args
|
|
697 The list of types.
|
|
698 @end table
|
|
699
|
|
700 @node radio-button-choice, item, menu-choice, Basic Types
|
|
701 @comment node-name, next, previous, up
|
|
702 @subsection The @code{radio-button-choice} Widget
|
|
703
|
|
704 Syntax:
|
|
705
|
|
706 @example
|
|
707 TYPE ::= (radio-button-choice [KEYWORD ARGUMENT]... TYPE ... )
|
|
708 @end example
|
|
709
|
|
710 The @var{type} arguments represents each possible choice. The widgets
|
|
711 value of will be the value of the chosen @var{type} argument. This
|
|
712 widget will match any value that matches at least one of the specified
|
|
713 @var{type} arguments.
|
|
714
|
|
715 The following extra properties are recognized.
|
|
716
|
|
717 @table @code
|
|
718 @item :entry-format
|
|
719 This string will be inserted for each entry in the list.
|
|
720 The following @samp{%} escapes are available:
|
|
721 @table @samp
|
|
722 @item %v
|
|
723 Replaced with the buffer representation of the @var{type} widget.
|
|
724 @item %b
|
|
725 Replace with the radio button.
|
|
726 @item %%
|
|
727 Insert a literal @samp{%}.
|
|
728 @end table
|
|
729
|
|
730 @item :buttons
|
|
731 The widgets representing the radio buttons.
|
|
732
|
|
733 @item :children
|
|
734 The widgets representing each type.
|
|
735
|
|
736 @item :choice
|
|
737 The current chosen type
|
|
738
|
|
739 @item :args
|
|
740 The list of types.
|
|
741 @end table
|
|
742
|
|
743 You can add extra radio button items to a @code{radio-button-choice}
|
|
744 widget after it has been created with the function
|
|
745 @code{widget-radio-add-item}.
|
|
746
|
|
747 @defun widget-radio-add-item widget type
|
|
748 Add to @code{radio-button-choice} widget @var{widget} a new radio button item of type
|
|
749 @var{type}.
|
|
750 @end defun
|
|
751
|
|
752 Please note that such items added after the @code{radio-button-choice}
|
|
753 widget has been created will @strong{not} be properly destructed when
|
|
754 you call @code{widget-delete}.
|
|
755
|
|
756 @node item, choice-item, radio-button-choice, Basic Types
|
|
757 @comment node-name, next, previous, up
|
|
758 @subsection The @code{item} Widget
|
|
759
|
|
760 Syntax:
|
|
761
|
|
762 @example
|
|
763 ITEM ::= (item [KEYWORD ARGUMENT]... VALUE)
|
|
764 @end example
|
|
765
|
|
766 The @var{value}, if present, is used to initialize the @code{:value}
|
|
767 property. The value should be a string, which will be inserted in the
|
|
768 buffer. This widget will only match the specified value.
|
|
769
|
|
770 @node choice-item, toggle, item, Basic Types
|
|
771 @comment node-name, next, previous, up
|
|
772 @subsection The @code{choice-item} Widget
|
|
773
|
|
774 Syntax:
|
|
775
|
|
776 @example
|
|
777 ITEM ::= (choice-item [KEYWORD ARGUMENT]... VALUE)
|
|
778 @end example
|
|
779
|
|
780 The @var{value}, if present, is used to initialize the @code{:value}
|
|
781 property. The value should be a string, which will be inserted in the
|
|
782 buffer as a button. Activating the button of a @code{choice-item} is
|
|
783 equivalent to activating the parent widget. This widget will only match
|
|
784 the specified value.
|
|
785
|
|
786 @node toggle, checkbox, choice-item, Basic Types
|
|
787 @comment node-name, next, previous, up
|
|
788 @subsection The @code{toggle} Widget
|
|
789
|
|
790 Syntax:
|
|
791
|
|
792 @example
|
|
793 TYPE ::= (toggle [KEYWORD ARGUMENT]...)
|
|
794 @end example
|
|
795
|
|
796 The widget has two possible states, `on' and `off', which corresponds to
|
|
797 a @code{t} or @code{nil} value.
|
|
798
|
|
799 The following extra properties are recognized.
|
|
800
|
|
801 @table @code
|
|
802 @item :on
|
|
803 String representing the `on' state. By default the string @samp{on}.
|
|
804 @item :off
|
|
805 String representing the `off' state. By default the string @samp{off}.
|
|
806 @item :on-type
|
|
807 Type representing the `on' state. By default an `item' widget displaying
|
|
808 the string specified with the @code{:on} keyword.
|
|
809 @item :off-type
|
|
810 Type representing the `off' state. By default an `item' widget
|
|
811 displaying the string specified with the @code{:off} keyword.
|
|
812 @end table
|
|
813
|
|
814 @node checkbox, checklist, toggle, Basic Types
|
|
815 @comment node-name, next, previous, up
|
|
816 @subsection The @code{checkbox} Widget
|
|
817
|
|
818 The widget has two possible states, `selected' and `unselected', which
|
|
819 corresponds to a @code{t} or @code{nil} value.
|
|
820
|
|
821 Syntax:
|
|
822
|
|
823 @example
|
|
824 TYPE ::= (checkbox [KEYWORD ARGUMENT]...)
|
|
825 @end example
|
|
826
|
|
827 @node checklist, editable-list, checkbox, Basic Types
|
|
828 @comment node-name, next, previous, up
|
|
829 @subsection The @code{checklist} Widget
|
|
830
|
|
831 Syntax:
|
|
832
|
|
833 @example
|
|
834 TYPE ::= (checklist [KEYWORD ARGUMENT]... TYPE ... )
|
|
835 @end example
|
|
836
|
|
837 The @var{type} arguments represents each checklist item. The widgets
|
|
838 value of will be a list containing the value of each ticked @var{type}
|
|
839 argument. The checklist widget will match a list whose elements all
|
|
840 matches at least one of the specified @var{type} arguments.
|
|
841
|
|
842 The following extra properties are recognized.
|
|
843
|
|
844 @table @code
|
|
845 @item :entry-format
|
|
846 This string will be inserted for each entry in the list.
|
|
847 The following @samp{%} escapes are available:
|
|
848 @table @samp
|
|
849 @item %v
|
|
850 Replaced with the buffer representation of the @var{type} widget.
|
|
851 @item %b
|
|
852 Replace with the checkbox.
|
|
853 @item %%
|
|
854 Insert a literal @samp{%}.
|
|
855 @end table
|
|
856
|
|
857 @item :buttons
|
|
858 The widgets representing the checkboxes.
|
|
859
|
|
860 @item :children
|
|
861 The widgets representing each type.
|
|
862
|
|
863 @item :args
|
|
864 The list of types.
|
|
865 @end table
|
|
866
|
|
867 @node editable-list, , checklist, Basic Types
|
|
868 @comment node-name, next, previous, up
|
|
869 @subsection The @code{editable-list} Widget
|
|
870
|
|
871 Syntax:
|
|
872
|
|
873 @example
|
|
874 TYPE ::= (editable-list [KEYWORD ARGUMENT]... TYPE)
|
|
875 @end example
|
|
876
|
|
877 The value is a list, where each member represent one widget of type
|
|
878 @var{type}.
|
|
879
|
|
880 The following extra properties are recognized.
|
|
881
|
|
882 @table @code
|
|
883 @item :entry-format
|
|
884 This string will be inserted for each entry in the list.
|
|
885 The following @samp{%} escapes are available:
|
|
886 @table @samp
|
|
887 @item %v
|
|
888 This will be replaced with the buffer representation of the @var{type}
|
|
889 widget.
|
|
890 @item %i
|
|
891 Insert the @b{[INS]} button.
|
|
892 @item %d
|
|
893 Insert the @b{[DEL]} button.
|
|
894 @item %%
|
|
895 Insert a literal @samp{%}.
|
|
896 @end table
|
|
897
|
|
898 @item :buttons
|
|
899 The widgets representing the insert and delete buttons.
|
|
900
|
|
901 @item :children
|
|
902 The widgets representing the elements of the list.
|
|
903
|
|
904 @item :args
|
|
905 List whose car is the type of the list elements.
|
|
906
|
|
907 @end table
|
|
908
|
|
909 @node Sexp Types, Widget Properties, Basic Types, Top
|
|
910 @comment
|
|
911 @section Sexp Types
|
|
912
|
|
913 A number of widgets for editing s-expressions (lisp types) are also
|
|
914 available. These basically fall in three categories: @dfn{atoms},
|
|
915 @dfn{composite types}, and @dfn{generic}.
|
|
916
|
|
917 @menu
|
|
918 * generic::
|
|
919 * atoms::
|
|
920 * composite::
|
|
921 @end menu
|
|
922
|
|
923 @node generic, atoms, Sexp Types, Sexp Types
|
|
924 @comment node-name, next, previous, up
|
|
925 @subsection The Generic Widget.
|
|
926
|
|
927 The @code{const} and @code{sexp} widgets can contain any lisp
|
|
928 expression. In the case of the @code{const} widget the user is
|
|
929 prohibited from editing edit it, which is mainly useful as a component
|
|
930 of one of the composite widgets.
|
|
931
|
|
932 The syntax for the generic widgets is
|
|
933
|
|
934 @example
|
|
935 TYPE ::= (const [KEYWORD ARGUMENT]... [ VALUE ])
|
|
936 @end example
|
|
937
|
|
938 The @var{value}, if present, is used to initialize the @code{:value}
|
|
939 property and can be any s-expression.
|
|
940
|
|
941 @deffn Widget const
|
|
942 This will display any valid s-expression in an immutable part of the
|
|
943 buffer.
|
|
944 @end deffn
|
|
945
|
|
946 @deffn Widget sexp
|
|
947 This will allow you to edit any valid s-expression in an editable buffer
|
|
948 field.
|
|
949
|
|
950 The @code{sexp} widget takes the same keyword arguments as the
|
|
951 @code{editable-field} widget.
|
|
952 @end deffn
|
|
953
|
|
954 @node atoms, composite, generic, Sexp Types
|
|
955 @comment node-name, next, previous, up
|
|
956 @subsection Atomic Sexp Widgets.
|
|
957
|
|
958 The atoms are s-expressions that does not consist of other
|
|
959 s-expressions. A string is an atom, while a list is a composite type.
|
|
960 You can edit the value of an atom with the following widgets.
|
|
961
|
|
962 The syntax for all the atoms are
|
|
963
|
|
964 @example
|
|
965 TYPE ::= (NAME [KEYWORD ARGUMENT]... [ VALUE ])
|
|
966 @end example
|
|
967
|
|
968 The @var{value}, if present, is used to initialize the @code{:value}
|
|
969 property and must be an expression of the same type as the widget.
|
|
970 I.e. the string widget can only be initialized with a string.
|
|
971
|
|
972 All the atom widgets take the same keyword arguments as the @code{editable-field}
|
|
973 widget.
|
|
974
|
|
975 @deffn Widget string
|
|
976 Allows you to edit a string in an editable field.
|
|
977 @end deffn
|
|
978
|
|
979 @deffn Widget file
|
|
980 Allows you to edit a file name in an editable field. You you activate
|
|
981 the tag button, you can edit the file name in the mini-buffer with
|
|
982 completion.
|
|
983
|
|
984 Keywords:
|
|
985 @table @code
|
|
986 @item :must-match
|
|
987 If this is set to non-nil, only existing file names will be allowed in
|
|
988 the minibuffer.
|
|
989 @end table
|
|
990 @end deffn
|
|
991
|
|
992 @deffn Widget directory
|
|
993 Allows you to edit a directory name in an editable field.
|
|
994 Similar to the @code{file} widget.
|
|
995 @end deffn
|
|
996
|
|
997 @deffn Widget symbol
|
|
998 Allows you to edit a lisp symbol in an editable field.
|
|
999 @end deffn
|
|
1000
|
|
1001 @deffn Widget integer
|
|
1002 Allows you to edit an integer in an editable field.
|
|
1003 @end deffn
|
|
1004
|
|
1005 @deffn Widget number
|
|
1006 Allows you to edit a number in an editable field.
|
|
1007 @end deffn
|
|
1008
|
|
1009 @deffn Widget boolean
|
|
1010 Allows you to edit a boolean. In lisp this means a variable which is
|
|
1011 either nil meaning false, or non-nil meaning true.
|
|
1012 @end deffn
|
|
1013
|
|
1014
|
|
1015 @node composite, , atoms, Sexp Types
|
|
1016 @comment node-name, next, previous, up
|
|
1017 @subsection Composite Sexp Widgets.
|
|
1018
|
|
1019 The syntax for the composite are
|
|
1020
|
|
1021 @example
|
|
1022 TYPE ::= (NAME [KEYWORD ARGUMENT]... COMPONENT...)
|
|
1023 @end example
|
|
1024
|
|
1025 Where each @var{component} must be a widget type. Each component widget
|
|
1026 will be displayed in the buffer, and be editable to the user.
|
|
1027
|
|
1028 @deffn Widget cons
|
|
1029 The value of a @code{cons} widget is a cons-cell where the car is the
|
|
1030 value of the first component and the cdr is the value of the second
|
|
1031 component. There must be exactly two components.
|
|
1032 @end deffn
|
|
1033
|
|
1034 @deffn Widget lisp
|
|
1035 The value of a @code{lisp} widget is a list containing the value of
|
|
1036 each of its component.
|
|
1037 @end deffn
|
|
1038
|
|
1039 @deffn Widget vector
|
|
1040 The value of a @code{vector} widget is a vector containing the value of
|
|
1041 each of its component.
|
|
1042 @end deffn
|
|
1043
|
|
1044 The above suffice for specifying fixed size lists and vectors. To get
|
|
1045 variable length lists and vectors, you can use a @code{choice},
|
|
1046 @code{set} or @code{repeat} widgets together with the @code{:inline}
|
|
1047 keywords. If any component of a composite widget has the @code{:inline}
|
|
1048 keyword set, its value must be a list which will then be spliced into
|
|
1049 the composite. For example, to specify a list whose first element must
|
|
1050 be a file name, and whose remaining arguments should either by the
|
|
1051 symbol @code{t} or two files, you can use the following widget
|
|
1052 specification:
|
|
1053
|
|
1054 @example
|
|
1055 (list file
|
|
1056 (choice (const t)
|
|
1057 (list :inline t
|
|
1058 :value ("foo" "bar")
|
|
1059 string string)))
|
|
1060 @end example
|
|
1061
|
|
1062 The value of a widget of this type will either have the form
|
|
1063 @samp{(file t)} or @code{(file string string)}.
|
|
1064
|
|
1065 This concept of inline is probably hard to understand. It was certainly
|
|
1066 hard to implement so instead of confuse you more by trying to explain it
|
|
1067 here, I'll just suggest you meditate over it for a while.
|
|
1068
|
|
1069 @deffn Widget choice
|
|
1070 Allows you to edit a sexp which may have one of fixed set of types. It
|
|
1071 is currently implemented with the @code{choice-menu} basic widget, and
|
|
1072 has a similar syntax.
|
|
1073 @end deffn
|
|
1074
|
|
1075 @deffn Widget set
|
|
1076 Allows you to specify a type which must be a list whose elements all
|
|
1077 belong to given set. The elements of the list is not significant. This
|
|
1078 is implemented on top of the @code{checklist} basic widget, and has a
|
|
1079 similar syntax.
|
|
1080 @end deffn
|
|
1081
|
|
1082 @deffn Widget repeat
|
|
1083 Allows you to specify a variable length list whose members are all of
|
|
1084 the same type. Implemented on top of the `editable-list' basic widget,
|
|
1085 and has a similar syntax.
|
|
1086 @end deffn
|
|
1087
|
|
1088 @node Widget Properties, Defining New Widgets, Sexp Types, Top
|
|
1089 @comment node-name, next, previous, up
|
|
1090 @section Properties
|
|
1091
|
|
1092 You can examine or set this value by using the widget object that was
|
|
1093 returned by @code{widget-create}.
|
|
1094
|
|
1095 @defun widget-value widget
|
|
1096 Return the current value contained in @var{widget}.
|
|
1097 It is an error to call this function on an uninitialized widget.
|
|
1098 @end defun
|
|
1099
|
|
1100 @defun widget-value-set widget value
|
|
1101 Set the value contained in @var{widget} to @var{value}.
|
|
1102 It is an error to call this function with an invalid @var{value}.
|
|
1103 @end defun
|
|
1104
|
|
1105 @strong{Important:} You @emph{must} call @code{widget-setup} after
|
|
1106 modifying the value of a widget before the user is allowed to edit the
|
|
1107 widget again. It is enough to call @code{widget-setup} once if you
|
|
1108 modify multiple widgets. This is currently only necessary if the widget
|
|
1109 contains an editing field, but may be necessary for other widgets in the
|
|
1110 future.
|
|
1111
|
|
1112 If your application needs to associate some information with the widget
|
|
1113 objects, for example a reference to the item being edited, it can be
|
|
1114 done with @code{widget-put} and @code{widget-get}. The property names
|
|
1115 must begin with a @samp{:}.
|
|
1116
|
|
1117 @defun widget-put widget property value
|
|
1118 In @var{widget} set @var{property} to @var{value}.
|
|
1119 @var{property} should be a symbol, while @var{value} can be anything.
|
|
1120 @end defun
|
|
1121
|
|
1122 @defun widget-get widget property
|
|
1123 In @var{widget} return the value for @var{property}.
|
|
1124 @var{property} should be a symbol, the value is what was last set by
|
|
1125 @code{widget-put} for @var{property}.
|
|
1126 @end defun
|
|
1127
|
|
1128 @defun widget-member widget property
|
|
1129 Non-nil if @var{widget} has a value (even nil) for property @var{property}.
|
|
1130 @end defun
|
|
1131
|
|
1132 @node Defining New Widgets, Widget Wishlist., Widget Properties, Top
|
|
1133 @comment node-name, next, previous, up
|
|
1134 @section Defining New Widgets
|
|
1135
|
|
1136 You can define specialized widgets with @code{define-widget}. It allows
|
|
1137 you to create a shorthand for more complex widgets, including specifying
|
|
1138 component widgets and default new default values for the keyword
|
|
1139 arguments.
|
|
1140
|
|
1141 @defun widget-define name class doc &rest args
|
|
1142 Define a new widget type named @var{name} from @code{class}.
|
|
1143
|
|
1144 @var{name} and class should both be symbols, @code{class} should be one
|
|
1145 of the existing widget types.
|
|
1146
|
|
1147 The third argument @var{DOC} is a documentation string for the widget.
|
|
1148
|
|
1149 After the new widget has been defined, the following two calls will
|
|
1150 create identical widgets:
|
|
1151
|
|
1152 @itemize @bullet
|
|
1153 @item
|
|
1154 @lisp
|
|
1155 (widget-create @var{name})
|
|
1156 @end lisp
|
|
1157
|
|
1158 @item
|
|
1159 @lisp
|
|
1160 (apply widget-create @var{class} @var{args})
|
|
1161 @end lisp
|
|
1162 @end itemize
|
|
1163
|
|
1164 @end defun
|
|
1165
|
|
1166 Using @code{widget-define} does just store the definition of the widget
|
|
1167 type in the @code{widget-type} property of @var{name}, which is what
|
|
1168 @code{widget-create} uses.
|
|
1169
|
|
1170 If you just want to specify defaults for keywords with no complex
|
|
1171 conversions, you can use @code{identity} as your conversion function.
|
|
1172
|
|
1173 The following additional keyword arguments are useful when defining new
|
|
1174 widgets:
|
|
1175 @table @code
|
|
1176 @item :convert-widget
|
|
1177 Function to convert a widget type before creating a widget of that
|
|
1178 type. It takes a widget type as an argument, and returns the converted
|
|
1179 widget type. When a widget is created, this function is called for the
|
|
1180 widget type and all the widgets parent types, most derived first.
|
|
1181
|
|
1182 @item :value-to-internal
|
|
1183 Function to convert the value to the internal format. The function
|
|
1184 takes two arguments, a widget and an external value, and returns the
|
|
1185 internal value. The function is called on the present @code{:value}
|
|
1186 when the widget is created, and on any value set later with
|
|
1187 @code{widget-value-set}.
|
|
1188
|
|
1189 @item :value-to-external
|
|
1190 Function to convert the value to the external format. The function
|
|
1191 takes two arguments, a widget and an internal value, and returns the
|
|
1192 internal value. The function is called on the present @code{:value}
|
|
1193 when the widget is created, and on any value set later with
|
|
1194 @code{widget-value-set}.
|
|
1195
|
|
1196 @item :create
|
|
1197 Function to create a widget from scratch. The function takes one
|
|
1198 argument, a widget type, and create a widget of that type, insert it in
|
|
1199 the buffer, and return a widget object.
|
|
1200
|
|
1201 @item :delete
|
|
1202 Function to delete a widget. The function takes one argument, a widget,
|
|
1203 and should remove all traces of the widget from the buffer.
|
|
1204
|
|
1205 @item :value-create
|
|
1206 Function to expand the @samp{%v} escape in the format string. It will
|
|
1207 be called with the widget as its argument. Should
|
|
1208 insert a representation of the widgets value in the buffer.
|
|
1209
|
|
1210 @item :value-delete
|
|
1211 Should remove the representation of the widgets value from the buffer.
|
|
1212 It will be called with the widget as its argument. It doesn't have to
|
|
1213 remove the text, but it should release markers and delete nested widgets
|
|
1214 if such has been used.
|
|
1215
|
|
1216 @item :format-handler
|
|
1217 Function to handle unknown @samp{%} escapes in the format string. It
|
|
1218 will be called with the widget and the escape character as arguments.
|
|
1219 You can set this to allow your widget to handle non-standard escapes.
|
|
1220
|
|
1221 You should end up calling @code{widget-default-format-handler} to handle
|
|
1222 unknown escape sequences, which will handle the @samp{%h} and any future
|
|
1223 escape sequences, as well as give an error for unknown escapes.
|
|
1224 @end table
|
|
1225
|
|
1226 If you want to define a new widget from scratch, use the @code{default}
|
|
1227 widget as its base.
|
|
1228
|
|
1229 @deffn Widget default [ keyword argument ]
|
|
1230 Widget used as a base for other widgets.
|
|
1231
|
|
1232 It provides most of the functionality that is referred to as ``by
|
|
1233 default'' in this text.
|
|
1234 @end deffn
|
|
1235
|
|
1236 @node Widget Wishlist., , Defining New Widgets, Top
|
|
1237 @comment node-name, next, previous, up
|
|
1238 @section Wishlist.
|
|
1239
|
|
1240 @itemize @bullet
|
|
1241 @item
|
|
1242 In general, we need @strong{much} better support for keyboard
|
|
1243 operations.
|
|
1244
|
|
1245 @itemize -
|
|
1246 @item
|
|
1247 It should be possible to add or remove items from a list with @kbd{C-k}
|
|
1248 and @kbd{C-o} (suggested by @sc{rms}).
|
|
1249
|
|
1250 @item
|
|
1251 @kbd{C-k} should kill to end of field or end of line, whatever come
|
|
1252 first.
|
|
1253
|
|
1254 @item
|
|
1255 Commands to move to the beginning/end of a field.
|
|
1256
|
|
1257 @end itemize
|
|
1258
|
|
1259 @item
|
|
1260 The @samp{[INS]} and @samp{[DEL]} buttons should be replaced by a single
|
|
1261 dash (@samp{-}). The dash should be a button that, when activated, ask
|
|
1262 whether you want to add or delete an item (@sc{rms} wanted to git rid of
|
|
1263 the ugly buttons, the dash is my idea).
|
|
1264
|
|
1265 @item
|
|
1266 Use graphical versions of the widgets for emacsen that can do that.
|
|
1267 I.e. real radio buttons and checkmarks instead of their @sc{ascii}
|
|
1268 equivalents.
|
|
1269
|
|
1270 @item
|
|
1271 There should be support for browsing the widget documentation.
|
|
1272
|
|
1273 @item
|
|
1274 There should be a way to specify that @key{RET} in a field will call the
|
|
1275 @code{:activate} function. This should be used by widgets such as
|
|
1276 @code{file} and @code{symbol} prompt with completion.
|
|
1277
|
|
1278 @item
|
|
1279 The @code{menu-choice} tag should be prettier, something like the abbreviated
|
|
1280 menus in Open Look.
|
|
1281
|
|
1282 @item
|
|
1283 The functions used in many widgets, like
|
|
1284 @code{widget-item-convert-widget}, should not have names that are
|
|
1285 specific to the first widget where I used them.
|
|
1286
|
|
1287 @item
|
|
1288 Unchecked items in a @code{radio-button-choice} or @code{checklist}
|
|
1289 should be grayed out, and the subwidgets should somehow become inactive.
|
|
1290 This could perhaps be implemented by binding @code{widget-inactive} to t
|
|
1291 when inserting the grayed out subwidget, and let the widget-specify
|
|
1292 functions check that variable.
|
|
1293
|
|
1294 @item
|
|
1295 Flag to make @code{widget-move} skip a specified button.
|
|
1296
|
|
1297 @item
|
|
1298 Document `helper' functions for defining new widgets.
|
|
1299
|
|
1300 @item
|
|
1301 Show button menus on mouse down.
|
|
1302
|
|
1303 @item
|
|
1304 Activate the item this is below the mouse when the button is
|
|
1305 released, not the item this is below the mouse when the button is
|
|
1306 pressed. Dired and grep gets this right.
|
|
1307
|
|
1308 @item
|
|
1309 Use @samp{@@deffn Widget} to document widgets.
|
|
1310
|
|
1311 @item
|
|
1312 Document global keywords in one place.
|
|
1313
|
|
1314 Document keywords particular to a specific widget in the widget
|
|
1315 definition.
|
|
1316
|
|
1317 Document the `default' widget first.
|
|
1318
|
|
1319 Split, when needed, keywords into those useful for normal
|
|
1320 customization, those primarily useful when deriving, and those who
|
|
1321 represent runtime information.
|
|
1322 @end itemize
|
|
1323
|
|
1324 @contents
|
|
1325 @bye
|